get_next_bmask

get next bitmask in the enum (bitfield)
     enum_id - id of enum
     bmask   - value of the current bitmask
returns: value of a bitmask with value higher than the specified
         value. -1 if no such bitmasks exist.
         All bitmasks are sorted by their values as unsigned longs.

long get_next_bmask(long enum_id, long value);